1. Field of the Invention
The present invention relates to a recovery for a metaloxidic cathodic active material for a lithium ion battery and a synthesis method for a metaloxidic cathodic active material for the lithium ion battery by the recovery method.
2. Background of the Invention
Using ternary cathodic active material (LiCo1/3Ni1/3Mn1/3O2 or LiNi0.5Co0.2Mn0.3O2) and binary cathodic active material (LiNi0.8Co0.18Al0.02O2) for high capacity lithium ion secondary batteries for electric vehicles, which are regarded in recent time, is expected to be increased. Hence, the need to reprocess (recover) or recycle the ternary and binary cathodic active materials from the waste lithium secondary batteries for the electric vehicles, which are expected to be generated in the future, is coming into the fore.
Considering methods for recovering metaloxidic cathodic active materials for the lithium icon secondary batteries, which have been reported so far, those methods employ a process of separating the cathodic active material from the waste lithium ion secondary battery, extracting the cathodic active material using hydrochloric acid (HCl), and precipitating the extracted cathodic active material using cobalt hydroxide (Co(OH)3) and nickel hydroxide (Ni(OH)2) for collection, or a process of dissolving the cathodic active material using sulfuric acid (H2SO4) or nitric acid (HNO3) under existence of hydrogen peroxide (H2O2), and separating and collecting cobalt and nickel using a neutralization-precipitation technology. Recently, a solvent extraction has also been used to extract cobalt and nickel from cathodic active material eluent.
Among other related art methods for dissolving the cathodic active material, a dissolving method using hydrochloric acid uses a strong acid upon an extraction process, which causes severe environmental pollution due to acid evaporated into the air, especially, causes serious problems, such as facility corrosion due to acid, and the like. Upon a dissolving process using sulfuric acid, since Co3+ as a main cathodic active material is more instable than Co2+ in a strong acid solution, merely using the sulfuric acid may result in an extremely low cobalt dissolution rate. To address such problem, more than 10% of hydrogen peroxide (H2O2), which is very expensive, should be input as a reductant to reduce Co3+ of the cathodic active material into Co2+ and more than 6M of concentrated sulfuric acid should be used to maintain a reaction temperature more than 70° C. In this case, economic efficiency may drastically be lowered due to excessive chemical costs and energy costs.